Business presentations are often subject to very strict time limits in meeting agendas. Not only are strict time limits often specified for a presentation, but often a presentation that was originally allowed a certain time frame, for example 30 minutes, may need to subsequently be altered due to the fact that the previous speaker went over (or under) the allotted time.
Another all too common scenario is that a person may suddenly be asked by their boss, last minute, to present a five minute summary of their 30 minute presentation at a meeting that will be starting in a few minutes.
While internal business presentations may specify a time limit and still be somewhat tolerant of a slight overage, there are other presentations, such as business pitches, where a presenter has exactly a specified number of minutes (e.g., five minutes) to present and, at the end of the time interval, the presenter must be done no matter how much more material was left to present.